Inkjet printing is commonly used for printing on paper or other types of print media and is generally a non-contact application of an ink to the print media. Typically, one of two types of ink jetting mechanisms are used and are categorized by technology as either drop on demand inkjet (DOD) or continuous inkjet (CIJ). The first technology, “drop-on-demand” (DOD) inkjet printing, provides ink drops that impact upon a recording surface using a pressurization actuator, for example, a thermal, piezoelectric, or electrostatic actuator. One commonly practiced drop-on-demand technology uses thermal actuation to eject ink drops from a nozzle. A heater, located at or near the nozzle, heats the ink sufficiently to boil, forming a vapor bubble that creates enough internal pressure to eject an ink drop. This form of inkjet is commonly termed “thermal inkjet (TIJ).”
The second technology commonly referred to as “continuous” inkjet (CIJ) printing, uses a pressurized ink source to produce a continuous liquid jet stream of ink by forcing ink, under pressure, through a nozzle. The stream of ink is perturbed using a drop forming mechanism such that the liquid jet breaks up into drops of ink in a predictable manner. One continuous printing technology uses thermal stimulation of the liquid jet with a heater to form drops that eventually become print drops and non-print drops. Printing occurs by selectively deflecting one of the print drops and the non-print drops and catching the non-print drops. Various approaches for selectively deflecting drops have been developed including electrostatic deflection, air deflection, and thermal deflection.
Additionally, there are typically two types of print media used with these inkjet printing systems. The first type is commonly referred to as a continuous web while the second type is commonly referred to as a cut sheet(s). The continuous web of print media refers to a continuous strip of media, generally originating from a source roll. The continuous web of print media is moved relative to the inkjet printing system components via a web transport system, which typically include drive rollers, web guide rollers, and web tension sensors. Cut sheets refer to individual sheets of print media that are moved relative to the inkjet printing system components via rollers and drive wheels or via a conveyor belt system that is routed through the inkjet printing system.
For highest productivity of these inkjet printing systems, it is common for the printing systems to use print modules which include an array of printheads to span the desired print width of the print media, so that the print media can be printed in a single pass of the print media past the print module. With such arrays of printheads there is a need to be able to service the print module, by removing, servicing and replacing a printhead from the array of printheads or of removing, servicing, and replacing of a component of one of the printheads. When the printheads or printhead components are installed in the print module, there is often a need to accurately position the serviceable unit relative to other portions of the print module. In many printing systems, there are space constraints that can hinder the task of removing and reinstalling the serviceable unit.
There is, therefore, a need for an improved system and method for securing and locating the serviceable unit in a print module of a printing system.